ASoC: fixes to caching implementations

This patch takes fixes a number of bugs in the caching code used by
several ASoC codec drivers. Mostly off-by-one fixes.

Signed-off-by: Ian Molton <ian@mnementh.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/codecs/wm8990.c b/sound/soc/codecs/wm8990.c
index 6b27786..f93c095 100644
--- a/sound/soc/codecs/wm8990.c
+++ b/sound/soc/codecs/wm8990.c
@@ -116,7 +116,7 @@
 	unsigned int reg)
 {
 	u16 *cache = codec->reg_cache;
-	BUG_ON(reg > (ARRAY_SIZE(wm8990_reg)) - 1);
+	BUG_ON(reg >= ARRAY_SIZE(wm8990_reg));
 	return cache[reg];
 }
 
@@ -129,7 +129,7 @@
 	u16 *cache = codec->reg_cache;
 
 	/* Reset register and reserved registers are uncached */
-	if (reg == 0 || reg > ARRAY_SIZE(wm8990_reg) - 1)
+	if (reg == 0 || reg >= ARRAY_SIZE(wm8990_reg))
 		return;
 
 	cache[reg] = value;